Conventional office chairs typically include a seat-back arrangement which is connected to a base or pedestal. Such seat-back arrangements often are connected to the base by a tilt control mechanism which permits tilting of the seat-back arrangement relative to the base to increase comfort for an occupant. In particular, a seat-back arrangement typically includes a seat assembly and a back assembly which are connected together by the tilt control mechanism wherein the seat assembly tilts forwardly and/or rearwardly relative to the base while the back assembly may either move in unison with the seat assembly or tilt independently of and relative to the seat assembly.
Such tilt mechanisms often include a lock mechanism which provides the ability to lock out forward and/or rearward tilting if desired by the occupant. In such an instance, a manually-actuatable handle is connected to the lock mechanism and is operable by the occupant to lock and unlock the tilt control mechanism. Many different actuator handles have been provided although some of these known handles have been relatively complex wherein a significant number of component parts have been used.
It is an object of the invention therefore to overcome the disadvantages associated with relatively complex actuator handles and provide an actuator handle which uses a minimum number of component parts and is easy to assemble.
The invention relates to an actuator handle for use with a tilt control mechanism of an office chair and in particular, the inventive actuator handle operates a tilt lock mechanism which locks and unlocks forward and/or rearward tilting of the chair. The actuator handle as disclosed herein is connected to the tilt lock mechanism although the actuator handle is also usable with other mechanisms of conventional tilt control mechanisms, for example, to lock out a sliding seat.
The actuator handle includes a housing and a rotatable shaft which are joined together without fasteners. In particular, the shaft includes a radial projection which fits through a keyed opening in the housing and then is rotated to prevent disengagement of the shaft from the housing.
To define positive positions, i.e. a locked position and an unlocked position, for the actuator handle, the inventive handle includes a camming arrangement between the shaft and housing. In particular, the end of the housing includes a V-shaped camming surface which cooperates with the radial projection wherein the radial projection both rotates and slides axially along the V-shaped camming surface during rotation of the shaft. A spring acts axially between the housing and shaft to resist axial movement of the shaft such that the radial projection snaps between locked and unlocked positions as it slides along the camming surface.
This arrangement provides a minimum number of component parts and is readily assembled together without fasteners by inserting the shaft into the housing and then rotating the shaft to move the radial projection into engagement with the camming surface.
Other objects and purposes of the invention, and variations thereof, will be apparent upon reading the following specification and inspecting the accompanying drawings.